Turkey's Minister for EU Affairs and Chief Negotiator Egemen Bagis speaks to the media during a press conference at the Turkish occupied area in northern part of divided capital Nicosia, Cyprus, Tuesday, Sept. 27, 2011. Turkish frigates and warplanes on Tuesday escorted a research ship to begin oil and gas exploration off the divided island of Cyprus, following a similar move by the Greek Cypriot government. (AP Photo/Harun Ucar)— AP

Turkey's Minister for EU Affairs and Chief Negotiator Egemen Bagis speaks to the media during a press conference at the Turkish occupied area in northern part of divided capital Nicosia, Cyprus, Tuesday, Sept. 27, 2011. Turkish frigates and warplanes on Tuesday escorted a research ship to begin oil and gas exploration off the divided island of Cyprus, following a similar move by the Greek Cypriot government. (AP Photo/Harun Ucar)
/ AP

ANKARA, Turkey 
Turkey is using its navy and air force to escort a ship conducting oil and gas exploration off Cyprus, an official said Tuesday, in the latest development in a dispute over the ownership of the divided island nation's natural resources.

Cyprus is split into an internationally recognized Greek Cypriot south and a breakaway Turkish Cypriot north. The southern government began exploratory drilling for oil and gas last week, prompting strong protests from Turkey, which doesn't recognize the Greek Cypriot administration.

In response, Turkey signed an oil and gas exploration deal with the Turkish Cypriots and sent a Turkish research ship to the Mediterranean to start exploration. The breakaway Turkish Cypriot state is only recognized by Turkey, which maintains 35,000 troops there.

Cyprus joined the European Union in 2004, but only its south enjoys membership benefits.

"We will try all channels of peace, but we will also protect our country's interests until the end," Prime Minister Recep Tayyip Erdogan of Turkey said Tuesday at an unrelated ceremony to mark the delivery of the first Turkish-made corvette warship to the navy.

The Turkish research ship, Koca Piri Reis, began its exploration Monday, but Turkish and Turkish Cypriots officials refused to reveal the ship's exact location then.

Umut Yenice, the captain of the Koca Piri Reis ship, told Turkey's state-run Anatolia news agency Tuesday that the vessel reached its destination about 50 miles (80 kilometers) off Cyprus the day before. He said the ship with 21 people aboard is in frequent contact with the escorting Turkish ships and planes.

Turkish Energy Minister Taner Yildiz said the research vessel is "where it is supposed to be," without providing details.

Cyprus Foreign Minister Erato Kozakou-Marcoullis questioned the ship's ability to search for undersea oil and gas deposits but said Cyprus was closely following the developments. "Certainly all these moves by Turkey on a military level are being monitored daily by our ministry," she said. Kozakou-Marcoullis also said her government was briefing unidentified international players "who must act at the appropriate moment."

In a telephone conversation with Erdogan on Monday, Greek Prime Minister George Papandreou urged "restraint" by all countries in the east Mediterranean, adding that Greece backs Cyprus' activities that remain within its sovereign rights.

Greece and Turkey disagree about areas for exploration for oil and gas in the Aegean and the Mediterranean. Turkey does not accept that islands have their own continental shelf, while Greece insists they do under international law.

The two countries came close to war in March 1987, when a Turkish research ship sailed into the Aegean Sea.

The current dispute also could jeopardize the island's long running reunification talks. Turkey said Greek Cypriots should avoid drilling or exploiting any possible discoveries until a peace accord has been reached, while Cyprus said Turkish Cypriots would eventually benefit from any fuel discovery.

The U.N.'s envoy for the divided island, Alexander Downer, urged for restraint to avoid derailing the peace talks and said the United Nations would consider mediating a resolution to the drilling dispute, if both sides asked for it.

Cyprus government spokesman Stefanos Stefanou rejected the offer, saying the exploratory drilling is unrelated to the peace talks and permitted under international law.